S4l physical CONSERVATIOlSr AND EESTORATION". 



an accumulation of well-established constant and liistorical facts, 

 from which we can safely reason upon all the relations of action 

 and reaction between man and external nature. 



But we are, even now, breaking up the floor and wainscoting 

 and doors and window frames of our dwelKng, for fuel to warm 

 our bodies and to seethe our pottage, and the world can not afford 

 to wait till the slow and sure progress of exact science has taught 

 it a better economy. Many practical lessons have been learned 

 by the common observation of unschooled men ; and the teach- 

 ings of simple experience, on topics where natural philosophy has 

 scarcely yet spoken, are not to be despised. 



In these humble pages, which do not in the least aspire to rank 

 among scientific expositions of the laws of nature, I shall attempt 

 to give the most important practical conclusions suggested by the 

 history of man's efforts to replenish the earth and subdue it ; and 

 I shall aim to support those conclusions by such facts and illus^ 

 trations only as address themselves to the understanding of every 

 inteUigent reader, and as are to be found recorded in works capa- 

 ble of profitable perusal, or at least consultation, by persons who 

 have not enjoyed a special scientific training. 



action is the interest of the association, not the conscience of the individual — 

 though composed of ultra-democratic elements, may become most dangerous 

 enemies to rational liberty, to the moral interests of the commonwealth, to tho 

 purity of legislation and of judicial action, and to the sacredness of private 

 lights. 



